Research on an image restoration method of cubic phase plate wave-front coding with mixed noise

Abstract

Wave-front coding (WFC) is a technique that adds a phase plate to an optical system's pupil exit surface. This technique first encodes the image so that the system's optical transfer function is insensitive to out-of-focus throughout a wide depth-of-focus (DoF), resulting in a blurred image. Furthermore, image noise would inevitably be generated because of device part failure or external interference. As a result, we would acquire a noisy and blurred image. The image needs to be restored to improve the imaging system's DoF. A series of experiments have been carried out to find the optimal image restoration solution. In this paper, we proposed a three-step image restoration scheme for noisy blurred images after cubic phase plate. At first, we used the Min-Max Average Pooling-based Filter (MMAPF) to remove salt-and-pepper noise. Then we used Shearlet to remove Gaussian noise. Finally, for image deblurring, we used the Amended Landweber (ALW) algorithm. Experiments on real infrared images show that this scheme has excellent performance and robustness for image restoration when applied to a cubic phase plate.